Backplate for a lighting fixture



FIG. 1 is a top front perspective view of a backplate for a lighting fixture showing my design;

FIG. 2 is a front elevational view;

FIG. 3 is a right side elevational view, the left side being a mirror image of the right side;

FIG. 4 is a rear elevational view;

FIG. 5 is a top plan view; and,

FIG. 6 is a bottom plan view.

The broken lines show the environment in which the article is used and are not considered part of the design claimed. 

The ornamental design for the backplate for a lighting fixture, as shown and described. 